Blasting composition containing a salt,liquid nitric ester and wetting agent



United States Patent U.S. Cl. 149-53 14 Claims ABSTRACT OF THE DISCLOSURE Explosive compositions in powder form characterized by their suitability for use in Wet situations comprising an explosive component, i.e., ammonium nitrate and/0r potassium nitrate and/or ammonium chloride in association with explosive sensitizing ingredients and namely from 3 to 20 wt.-percent of at least one liquid nitric ester referred to the explosive mixture and 0.001 to 1 wt.-percent of a wetting agent referred to the water soluble components of the explosive mixture, the latter wetting agents rendering the water-soluble components of the explosive composition wettable by the nitric esters.

A process of waterproofing and sensitizing explosive compositions containing ammonium nitrate and/ or potassium nitrate and/ or ammonium chloride is also disclosed, the same comprising incorporating into such a composition at least one liquid nitric ester and a wetting agent.

This invention relates to explosive compositions which do not deteriorate in sensitiveness when used in wet situations.

It is well known that the ammonium nitrate blasting explosives and particularly ammonium nitrate powder explosives have a serious defect occasioned by the extreme water solubility and hygroscopicity of ammonium nitrate. This for instance leads to the rapid detonation of cartridges containing ammonium nitrate powder when the shots are laid in wet situations. The ammonium nitrate in the aforesaid kind of explosives has been replaced partially or entirely by equivalent amounts of sodium nitrate and ammonium chloride. The resulting explosive compositions, however, are still hygroscopic and quickly deteriorate in sensitiveness when used in wet situations.

It 'is in the prior art to waterproof the water soluble components of explosive mixtures in powder form, such as potassium nitrate, ammonium nitrate or ammonium chloride, by means of long-chained fatty acid salts and fatty amine salts, which are added in relatively small amounts as for example, 0.01 to 0.15% of the weight of the water-soluble explosive components. Larger quantities have a disadvantageous effect in that they have an adverse influence on the physical properties involved in detonation.

It is also in the prior art to add liquid nitric acid esters as sensitizers to explosive mixtures. The wetting action of nitric esters on the water-soluble explosive components, however, is relatively poor.

In accordance with the invention it has now been found that waterproof explosive compositions in powder form which are satisfactorily sensitive to detonation are obtained by combining as explosive ingredient at least one member selected from the group consisting of ammonium nitrate, alkali nitrate and ammonium chloride, at least one liquid explosive sensitizing ingredient, i.e., nitroglycerine,

nitroglycol, diglycol dinitrate, dinitrochlorohydrin, nitro- 7 pentaerythritol, said liquid nitric ester being used in an amount of from 3 to 20% and preferably 5 to 15% referred to the explosive composition and from 0.001 to 1% and preferably 0.05 to 0.5% of the weight of the water soluble explosive ingredient of a wetting agent, the latter serving to render the water soluble explosive ingredient wettable by the nitric esters.

Surprisingly it has been found in accordance with the invention that the physical properties of the explosive mixture which are involved in detonation are considerably improved by the additives of the invention as a better distribution of the sensitizer is achieved by means of the wetting, along with the water-proofing of the water-soluble components of the explosive.

Instances of nitric esters suitable for use herein are, for example, the following: nitroglycerin, dinitrochlorohydrin, nitroglycol and diethylene glycol dinitrate.

The compounds which are suitable for use as wetting agents are characterized in that they contain one radical that is soluble in the nitric esters and one that is insoluble in the nitric esters and which is adherent to the watersoluble components of the explosive. Example-s of radicals which are soluble in nitric esters are, for example, oxazolinyl, benzoylacetonyl, naphthyl, naphthyloxy, benzolazo and phenyl. Instances of radicals which are insoluble in nitric esters and which are adherent to the watersoluble components of the explosive are, for example, a parafiin radical, which may contain halogen or nitro group substituents, or a metal cation.

In the oxazoline derivatives (1) and (II):

x can represent a whole number of from 3 to 18 and y a whole number of from 1 to 18.

Two oxazoline radicals can also be attached to an alkylene radical, as for example, in a,w-bis-(2-phenyl-4- methyloxazolinyl-4 -dotriacontane:

(III) Further examples of suitable wetting agents include the following: 2-naphthyloxyacetic acid laurylamide, 2- naphthylstearylamine, sodium benzenesulfonate, sodium benzoate, the copper salts of benzoylacetone:

and the copper salts of benzolazonaphthene:

It is particularly preferred to use those wetting agents which simultaneously prevent deflagration, thereby achieving greater safety against firedamps in blasting operations.

3 The invention will be further illustrated by a detailed description in connection with the following specific examples of the practice of it. The examples are, however, in no wise to be construed as limiting the scope of the invention.

(b) An explosive mixture having the same composition as under (a), but with the difference that 10 g. of Vaseline (petroleum jelly) is used in place of the oxazoline wax, and

(c) An explosive mixture as under (a), but without the blasting gelatin, were prepared and subjected to a series of explosive test procedures.

The preparation of the explosive mixture was carried out in the following manner:

10 g. of oxazoline wax or Vaseline (petroleum jelly) were mixed with 100 g. of ammonium chloride and then this mixture admixed with the remaining components. The axazoline wax was wetted by the blasting gelatin, but not by water. The Vaseline, on the other hand, was wetted neither by the blasting gelatin nor by water. The following table shows the test data obtained:

TABLE 1 Explosive Mixture a b c Cartridge density in g./ccm 1. 17 1. 17 1. 28 Cartridge diameter in mm 30 30 Compression according to Hess in mm 4. 1 3. 1 Water resistance in cm./min 1 50/60+ 2 50/30 One drop of water remains on substance for minutes 0 The cartridge is not parafiined.

1 50/60+ Indicates that 4 cartridges were still detonatable after having lain 50 cm. underwater for 60 minuts.

2 50/30- Indicates that 4 cartridges were no longer detonatable after having lain underwater at a depth of 50 cm. for 30 minutes.

Potassium nitrate 80% (grain size under 0.1

Hydrate of alumina 12 Blasting gelatin (as in Example 1) 320 Collodion cotton 0.4 Finely powdered silicic acid 0.4 Galactomannitol 38 (b) An explosive mixture as under (a), but without oxazoline wax were prepared and subjected to explosive test procedures.

The preparation of the explosive mixture was carried out as follows: The oxazoline wax and fatty amine salts were melted together. The resulting mixture was then wetted with blasting gelatin. The mixture thus obtained was thereafter mixed with ammonium chloride and potassium nitrate and finally with the remaining components.

The following table sets out the results which were obtained.

Deilagration test carried out in the Biehl bomb 2 The cartridge was not paraifined.

1 Represents detonation transmission.

Represents no detonation transmission.

2 2% cartridges (approx. 270 g.) of Wetter-Carbonit B were brought to detonation on the bottom of the Bichl bomb. A perforated plate was placed on the bomb, and the explosive being evaluated (a) and the one being used for comparison (b) were placed on the plate at a distance of approximately 10 cm. from one another.

3 N o deflagration; cartridge intact, ammonium chloride and potassium nitrate crystals still visible.

4 Deflagration; cartridge deformed by chemical reaction. No ammonium chloride or potassium nitrate crystals visible.

Example 3 (a) An explosive was prepared as follows from:

G. Copper acetate-1H O 10 Ammonium chloride 1360 Potassium nitrate 2620 Blasting gelatin (as in Example 1) 400 Benzoyl acetone l0 Collodion cotton 0.45 Hydrate of alumina 20 Wood meal 20 Galactomannitol 60 TABLE 3 Explosive Mixture a b Cartridge density in gJccm. Cartridge diam. in mm Compression according to Hess in mm.

4.3 4.0 Water resistance in cm./m1n /60+ 50/20- Cartridge was not parailined.

100/60+ Designates that 4 cartridges were still detonatable after having lain under water at a depth of 100 cm. for 60 minutes.

50/20- Means that 4 cartridges were no longer dctonatable after having lain 50 em. under water for 20 minutes.

Example 4 (a) An explosive was prepared from:

G. Copper acetate-H O 17 Ammonium chloride 1360 Potassium nitrate Blasting gelatin (as in Example 1) 1-benzolazo-naphthol-2 Acetone Collodion cotton Wood meal 20 Hydrate of alumina 20 Galactomannitol 60 TABLE 4 Explosive Mixture a b Cartridge density in g./ccm 1. 24 1. 29 Cartridge diam. in mm 30 30 Compression according to Hess in mm 6.0 3. 9 Water resistance in cm./min 100/60+ 50/20- lhe cartridge was not parafiined.

100/60+ Designates that 4 cartridges were still detonatable after lying under water at a depth of 100 cm. for 60 minutes.

50/20- Designates that 4 cartridges were no longer detonatable after lying 50 cm. under water for 20 minutes.

Example 5 (a) An explosive mixture was prepared by mixing together the following:

G. Ground ammonium nitrate 3132 Ox-azoline wax (as in Example 1) 16 Dinitrotoluene 80 Trinitrotoluene 480 Wood meal 80 Coloring components 8 Blasting gelatin (as in Example 1) 240 (b) A comparison explosive was prepared which contained 0.40% parafiin in place of the wetting agent. The data which appears in the following table was obtained when these explosives were subjected to testing:

TABLE 5 Explosive Mixture a Cartridge in mm 30 50 cm. under water for 60 minutes.

4 cartridges were kept 100 cm. under water for 60 Detonation transmission still occurred at a cartridge distance of 10 cm.

minutes.

Example 7 (a) An explosive was prepared using the following components:

Sodium benzene sulfonate 4 Ammonium chloride 20 Potassium nitrate 70% (grain size under 0.1 mm.) 2327 Ammonium chloride 65% (gnain size under 0.1

mm.) 1220 Hydrate of alumina 100 Finely powdered silicic acid l Blasting gelatin 350 Galactomannitol 38 The explosive was prepared in the following manner: 4 g. of sodium benzene sulfonate were mixed together with 20 g. ammonium chloride, and this mixture was then mixed with the remaining components.

('b) An explosive was prepared for use as a comparison but contained no sodium benzene sulfonate.

The test data obtained using these two explosives is summarized in the following table:

TABLE 7 Explosive Mixture a b Cartridge density in gJcm 1.10 Compression according to Hess in mm 3.1 2. 3 Water resistance in cm./min 1 60 10F 30 Detonation transmission still occurred at a cartridge distance of 5 cm., but not at 6 cm.

Detonation transmission ceased beyond a cartridge distance of 6 cm.

The cartridge was not paraflined.

Example 6 (a) An explosive mixture as set out in Example 5 was prepared but the oxazoline wax was replaced by a mixture of oxazoline wax and fatty amine salts (as in Example 2) in a weight ratio of 3:2. This mixture was also wet by blasting gelatin.

Example 8 (a) An explosive was made from the following components:

b An 1 d f Ammonium chloride 1240 exp osivewas prepare 01 I156 38 a COIIIPH 'I H Hydrate of alumina 100 explosive and contained 0.40 wt.-percent panaflin instead Finely powdered ili i acid 1 of the wetting agent. In the following table the test da Blasting gelatin 350 which was obtained with these explosives is set out. Galactomannitol 38 TABLE 6 Explosive Mixture a b Cartridges in mm 30 30 Water resistance in cm./min.: 4 cartridges were held Detonation transmission Detonation transmission under water at a depth of 50 cm. for min. still occurred afterward still occurred afterward at 12 cm. spacing.

min.

spacing.

at 5 cm. spacing, but not at 6 cm. spacing.

Detonation transmission no logner occurred thereafter at a spacing of 0 cm.

The cartridge was not paraflined.

following table:

TABLE 8 Explosive Mixture a b Cartridge density in g./crn 1.15 1. l2 Compression according to Hess in mm 2. 7 2. 3 Water resistance in cur/min 1 50/60 2 10/30 1 Still detonates it the cartridges were adjacent one another. 2 N longer detonates even it cartridges were adjacent one another.

We claim: 1. A blasting explosive composition comprising: (1) a Water soluble explosive component comprising at least one member selected from the group consisting of ammonium nitrate, alkali nitrate and ammonium chloride, (2) 3 to 20 wt.-percent referred to the total explosive composition of a liquid nitric ester, and (3) 0.001 to 1 wt.-percent referred to said watersoluble component comprising a compound containing one radical which is soluble in said nitric ester and one radical which is insoluble in said nitric ester and which is adherent to said explosive component., said wetting agent rendering said explosive component Wettable by said liquid nitric ester.

2. A blasting explosive composition according to claim 1 wherein said liquid nitric ester is present in an amount of from 5 to 15 wt.-percent referred to the explosive composition.

3. A blasting explosive composition according to claim 1 wherein said liquid nitric ester is at least one member selected from the group consisting of nitroglycerin, dinitrochlorohydrin, nitroglycol and diethylene glycol dinitrate.

4. A blasting explosive composition according to claim 1 wherein said wetting agent is present in an amount of 0.05 to 0.5 wt.-percent referred to the explosive component.

5. A blasting explosive composition according to claim 1 wherein said wetting agent is a member selected from the group consisting of wherein R is a member of the group consisting of 2 x" 3,

wherein at is a whole number of from 3 to 18 and y is a whole number of from 1 to 18,

wherein p has a value of from 2 to 40, 2-naphthyloxyacetic acid laurylamide, Z-naphthylstearylamine, sodium benzene-sulfonate, sodium benzoate,

and

6. A blasting explosive composition according to claim 1 additionally containing at least one member selected from the group consisting of wood meal, urea, guanidine nitrate, argillaceous earths, china clay, wheat flour, water-soluble carboxymethyl cellulose, galactomannitol copper acetate.

7. A blasting explosive composition according to claim 1 comprising:

G. Oxazoline wax (a mixture of 8 parts by weight of on w bis (2 phenyl 4 methyloxazolinyl-4)- dotriacontane and 2 parts by weight of a (2- phenyl 4 methyloxazolinyl 4)-tetratriacontane) 10 Ammonium chloride 1509 Potassium nitrate 2630 Hydrate of alumina 20 Blasting gelatin consisting of a mixture of 60% by Weight of nitroglycerin and 40% of nitroglycol 355 Galactomannitol 30 8. A blasting explosive composition according to claim 1 comprising:

9. A blasting explosive composition according to claim 1 comprising:

G. Copper acetatelH O l0 Ammonium chloride 1360 Potassium nitrate 2620 Blasting gelatin (60% by weight of nitroglycerin and 40% by weight nitroglycol) 400 Benzoyl acetone 10 Collodion cotton 0.45 Hydrate of alumina 20 Wood meal 20 Galactomannitol 60 10. A blasting explosive composition according to claim 1 comprising:

G. Copper acetate-H O 17 Ammonium chloride 1360 Potassium nitrate 2620 Blasting gelatin (60% by weight of nitroglycerin and 40 by weight nitroglycol) 400 1-benzolazo-naphthol-2 10 Acetone 15 Collodion cotton 0.45 Hydrate of alumina 20 Wood meal 20 Galactomannitol 60 11. A blasting explosive composition according to claim 1 comprising:

12. A blasting explosive composition according to claim 1 comprising:

Sodium benzene sulfonate 4 Ammonium chloride 20 Potassium nitrate 70% (grain size under 0.1 mm.) 2327 Ammonium chloride 65% (grain size under 0.1

mm.) 1220 Hydrate of alumina 100 Finely powdered silicic acid 1 Blasting gelatin (60% by weight nitroglycerin and 40% by weight nitroglyc'ol) 350 Galactomannitol 38 13. A blasting explosive composition according to claim 1 comprising:

Sodium benzoate 4 Potassium nitrate 2326.7

Ammonium chloride 1240 Hydrate of alumina 100 G. Finely powdered silicic acid 1 Blasting gelatin 60% by weight nitroglycerin and by weight nitroglycol) 350 Galactomannitol a 3 8 14. A method for preparing a blasting explosive which is non-hydroscopic and does not deteriorate in sensitiveness when used in wet situations comprising forming a mixture of (1) a water soluble explosive component comprising at least one member selected from the group consisting of ammonium nitrate, alkali nitrate and ammonium chloride, (2) 3 to 20 wt.-percent referred to the total explosive composition of a liquid nitric ester, and

(3) 0.001 to 1 wt.-percent referred to said water-soluble component comprising a compound containing one radical which is soluble in said nitric ester and one radical which is insoluble in said nitric ester and which is adherent to said explosive component,

said wetting agent rendering said explosive component wettable by said liquid nitric ester.

References Cited UNITED STATES PATENTS 2,991,167 7/1961 Burton 14919 3,073,730 1/1963 Doe et al 149-19 3,118,797 1/1964 Colfee 1494 X 3,215,573 11/1965 Winkler 149--19 X 3,260,631 7/1966 Witz et a1 149l9 X CARL D. QUARFORTH, Primary Examiner.

S. I. LECHERT, Assistant Examiner.

U.S. Cl. X.R. 

